It’s Oscar time, one of those rare times of year when lay moviegoers ponder what qualifies as great acting even as they become aware that movies involve something called “sound mixing.” They look at lists of acting nominees, and get the impression that an award-worthy performance is something that involves a) mimicking a famous person; b) affecting some sort of accent or funny voices, otherwise known as the “Rain Man rule”; or c) dying and/or mourning over someone who has died. The formula for plaudits has become so schematic, you could practically develop a mathematical formula to determine who will win in any given Oscar category (Hint: guess who many of the above apply to Phillip Seymour Hoffman in Capote).

What does any of this have to do with 16 Blocks, a bad cops/slightly-less-bad cops thriller from Lethal Weapon director Richard Donner? Surprisingly enough, this simple genre exercise offers a lesson in what some actors work too hard to do in order to convince you that they’re giving a great film performance—and what other actors seem to be able to do without breaking a sweat.

Case study #1: Bruce Willis. After starting his career as the smirking tough guy in action movies like Die Hard and The Last Boy Scout, Willis has spent most of the last decade trying to build his bona fides as a serious actor. Here he plays Jack Mosley, a sad sack of an alcoholic NYPD detective on the down side of his career. It’s the kind of character role that many actors could slip into, but there’s nothing natural about what Willis does. He lets his gut go paunchy over his belt buckle; he walks with a pronounced limp. There’s nothing terrible about the performance, but there’s always the sense that he needs the gimmicks to prop him up. There’s effort in every moment, right down to the whispered rasp that’s Willis’ “tipped pitch” that for essaying Drama in much the same way Robin Williams’ beard is for him.

Case study #2: Mos Def. The hip-hopper/actor has shown flashes of brilliance in his film career, including a turn as the cop on Kevin Bacon’s tail in The Woodsman. In 16 Blocks he’s Eddie, a career small-time criminal who’s about to testify against several of the city’s crooked cops. Unfortunately, his assigned escort Jack has only two hours to take him the 16 blocks from lockup to courthouse before the grand jury dissolves, and those same crooked cops are eager to put a bullet in Eddie’s head. The motor-mouthed Eddie is supposed to be a buddy-foil for the taciturn Jack, but the role gives Def no chance to show his charisma. It almost seems as though Donner showed him Joe Pesci’s performances in the Lethal Weapon movies and said, “Be that guy.”

Case study #3: David Morse. He’s been around for 25 years, and all he has done is build a body of stellar character work that has guaranteed that most viewers almost sort of know who he is. As Frank, Jack’s one-time partner and the ringleader of 16 Blocks’ corrupt badges, Morse gives the kind of performance that feels like it belongs in another kind of movie. It’s intense but unaffected, villainous but never Villainous. As has been true for most of his career, there’s never a moment when you can catch Morse acting—he inhabits roles so thoroughly that watching him can make a movie feel better than it is.

16 Blocks doesn’t need Morse to rescue it from incompetence. Donner knows how to craft this kind of movie in his sleep, even if he’s dealing with the kind of Movie World script that never bothers to explain how someone just happens to have a roll of duct tape on a city bus. It’s solid but unspectacular, and sometimes seems to be trying a bit too hard. And you could say the same about a couple of the lead performances.

16 BLOCKS

**.5 (two and a half stars)

Starring Bruce Willis, Mos Def, David Morse

Directed by Richard Donner

Rated PG-13